An emerging service delivery model of integrating health and social care for older people has been actively promoted by the Chinese government since 2016, but the client experience and influencing mechanism still remain unclear. Methods: this study adopts a qualitative methodology to delve deeper into the factors and mechanism shaping the client experience of residential integrated health and social care for older people in the Chinese context, so as to understand the experiences of older residents during the whole process of receiving integrated care services, and on this basis, put forward suggestions for the improvement of a high-quality aged care service system. We coded and analyzed the in-depth interview data of twenty older adults and six staff members from June 2019 to February 2020, recruited from six institutions in Changsha, one of the ninety pilot cities for integrated health and social care in China. Results: the findings showed that the client experience of older adults is mainly affected by factors in three dimensions (scene construction, individual minds, and interaction and communication), which are comprised of six sub-categories (social foundation, institutional functions, perception and emotion, cognition and understanding, intimacy and trust, and participation). Based on the factors and mechanism (consisting of six influencing paths), we constructed a model of the client experience of integrated health and social care for older people in the Chinese population. Conclusions: the factors and mechanism influencing the client experience of integrated health and social care for older people are complex and multifaceted. Attention should be paid to the direct effects of perception and emotion, institutional functions, intimacy and trust in the client experience, and the indirect effects of social foundation and participation on the client experience.